Governor control mechanism



May 23, 1939. E, MCCQRW K 2,159,283

GOVERNOR CONTROL MECHANISM Filed Aug. 22, 1935 LH 2Q, 55 Q an 33 29 22 50 I I H) I L 1 11v VENTOR 5M fie mu'z' 6M1 a 22 ma] A TTORNE ye.

Patented May 23, 1939 I UNITED STATES GOVERNOR CONTROL MECHANISM Elmer McCormick, Waterloo, Iowa, assignor to John Deere Tractor Company, Waterloo, Iowa,

a corporation of Iowa Application August 22,

11 Claims.

The present invention relates generally to tractors and similar machinery and is principally concerned with the provision of a new and improved governor conti'ol mechanism whereby the action of the tractor governor is made more accurate and the speed of the tractor motor can be kept more nearly uniform than has heretofore been practical.

Farm tractors and the like are usually supplied withgovernors suitably connected with the throttle valve of a carburetor and adjustable spring means so as to automatically maintain the correct engine speed under varying load conditions, adjustment of the spring tension serving to cause the motor to run faster or slower. However, in prior structures of which I am aware, the various forms of linkage employed have em- .bodied springs and other parts movable on or within one another during the action of the governor in adjusting the position of the carburetor throttle to maintain uniform engine speed. In order to keep the governor linkage parts from binding and to prevent variations due to friction of the associated parts from affecting the action of the engine, it was necessary to frequently examine the linkage in order to .keep the parts free from dirt and to correct for any binding or friction at any point from the opening to the closing position of the carburetor throttle.

With these factors in mind, the principal ob ject of the present invention contemplates the construction and arrangement of a governor control linkage so that the possibility of binding and excessive friction is entirely eliminated without in any way affecting the sensitiveness of the control by the engine governor. Specifically, it is an object of the present invention to provide spring biasing means, against which the governor normally acts, so arranged and constructed that the spring is connected directly with the governor arm and with the manually set leverby a simple pivotal connection, whereby practically all friction is eliminated and no unnecessary sliding of one part on another present.

Still furthen-a'nother object of the present invention contemplates the use of a spring means so constructed and connected with the manually adjustable part that the reaction of the spring bias against the governor arm is taken by bearing-surfaces in alignment with the direction of the force of.the spring. This serves to eliminate all tendency for cocking of one part with respect to the other and otherwise eliminates excessive and uneven wear due to eccentrlcally applied forces. An additional object of the present in- 4 193s, Serial No. 37,281

' vention, taken in conjunction with the accompanying drawing illustrating such embodiment.

In the drawingz V Figure 1 is a. top plan view of a portion of the power plant and associated parts of afarm tracll tor of the two cylinder horizontal type and embodying the present invention;

Figure 2 is a section taken along the line 2-2 of Figure- 1; k

Figure 3 is a section taken along the line 3-3 of Figure 2;

Figure 4 is an enlarged plan view of the governor arm and associated leaf spring; and

Figure 5 is a section taken substantially along the line 55 of Figure 1, with certain parts shown in elevation.

Referring now more particularly to Figures 1 and 2, the reference numeral [0 indicates the tractor motor in its entirety. The motor I0 is provided with a combined crank case and trans- .missionhousing H in which is journaled the motor crank shaft-upon which the fly wheel I! is mounted. On the end opposite the fly wheel l2, the crank shaft carries a belt pulley l3. The motor I0 is provided with a manifold I5 to which is connected a carburetor l6 of conventional construction and provided with a throttle valve ll.

The governor mechanism for the tractor is indicated in its entirety by the reference numeral 20 and includes a governor housing 2| mounted on the top of the motor block II, as best shown in Figure 2, by any suitable means, such as bolts or cap screws 22. The present invention is not particularly concerned with the details of the governor, itself, and it will therefore suflice to note that a shaft 25 is journaled within the housing 2| upon bearings li and 21 and carries at one end a. pinion 28 which meshes with a gear 29 connected with or forming a part of the transmission system of the tractor so as to be driven at a speed proportional to the speed of rotation of the engine. Fixed to the shaft 25 is a gear 30 which not only serves'to drive a fan shaft 3| (Figure 1) but is provided. with ears 3! which 55 of a thrust'bearing 4| to the rounded bifurcatedend 42 of an arm 43 mounted on a vertically disposed governor shaft 44, the upper end of which projects out through the top of the governor housing2|.' The' arm 43 is preferably secured to the governor shaft 44 by means of screws 45, and the vertically disposed shaft 44 is journaled for rocking motion in bosses 41 and 48 formed in the housing 2|. I

The governor arm, that is, the member movable in response to variations in the speed of rotation of the motor I0, is indicated in its entirety by the reference numeral 5|] and comprises 1 a rigid section 5| having an apertured boss 52 at its innerend the opening 53 of which is adapted 5 to receive the upper end of the governor shaft 44.

The other part of the governor arm 56 consists of a flat leaf spring 55 having a long taper and mounted at its inner end in a notch or groove 56 extending generally longitudinally of the governor arm section 5|. Preferably, the inner end of the spring fits snugly within the side wall portions of the groove 56 and is held fixedly in place therein by a spring clamp 58. Both the inner end of the spring 55 and the spring clamp 5 58 are provided with an' opening formed therein to receive a set screw 60 which is threaded into another opening 6| formedin the boss portion 52 of the rigid governor 'arm 5| and intersecting the opening 53. A nut 62 threaded onto the outer portion of the set screw 60- servesto securely hold the spring clamp 58 and the spring 55 in'position, the set screw 60 serving to fixedly secure thev governor arm150 to the upper end'of the governor shaft 44 so as to swing with the a latter. A'projection 65 is formed onthe outer ,end of the governor arm 5| at substantially right angles to the axis of the arm and is eng eable with the outer end portion of the'spring 55 so as to limit the relative movement between the most end of the spring 55 is formed with an eye 66 to receive oneend of arod 61. Similarly, the

outermost end of the rigid governor arm section 5| is provided with an opening to receive an end u of another rod 69.

As best shown in Figure 1, therod 61 is utilized as. a connection between the outermost end of the spring 55 and ahand throttle unit 18 mounted on a bracket 1| carried at theupper on end of the steering column 12 (Figure 5) of the tractor. The hand throttle unit includes an arm 13 which is adapted tobe adjustably mounted so as to be retained in any position to which it may be moved for the purpose of determining the speed of the tractor motor. Preferably, the hub "Ia of the lever 16 is arranged to fit into a. tapered socket formed in thebracket 1|, and a spring 16 is biased between the upper end of the spindle portion of the arm 13 and the bracket 1| 70 for the purpose of'maintaining frictional engagement between the lever 10 and the bracket '1l The outer end-of the arm 13 is provided with an opening to receive the angularly bent endof a sleeve member 14 which is mounted lljl pon the threaded end 15 of the rod 61 and parts 5| and 55 in one direction, and the outerthereby serves as apart of the latter. The end of the rod 61 opposite the end 15 and the part 14 thereof is also bent angularly, as at 11in Figure 2, and this latter endis disposed in the eye 66 at the outermost end of the spring 55. Suit- 5 able washers andv cotter keys 16 are preferably employed for holding the spring and rod in proper position.

The governor arm 5| -is connectedwith the throttle valve H, as aforesaid, by the rod 69, and 0 the rear end of this member is bent angularly and "by this means is pivoted to the outer end of the throttle arm H. The opposite or forward end of the rod 69 carries a fitting or sleeve member 86 which is similar to the member 14 de- 15 .scribed above and is also provided with an angularly bent end 8|, a lock nut 82 being disposed on the threaded end of the rod 69 for the purpose of locking the member 80 in adjusted position. w The member 14 on the rod 61 is similarly secured 20 r in adjusted relation on the rod 61.

In operation, 'the' governor weights 35 move outwardly in proportion'to the rate of rotation of the shaft 25, rocking the shaft 44 and the governor arm 50. The spring 55, anchored to 25 the hand throttle unit 10 by the rod 61, exerts a bias resisting the rocking of the shaft 44 and arm 5| and, in connection with the setting of the hand throttle unit 18, determines the amount .of rocking movement which the rigid governor arm 0 section 5| experiences for a given rate of speed of the engine I8. Swinging movement .of the arm- 5|, which is in the direction of the arrow shown in Figure 1*as the spring 55 yields, causes the throttle valve H to move towards its closed 35 .position. By virtue of this construction, when the tractor is operating under load the speed of the engine remains substantially constant, for. as the load lightens and the motor tends to speed up, the weights 35 move outwardly andswing 40 the arm 5| in a counterclockwise direction as projection 65 thereby serving as a stop, acting through the rod 61and the hand lever unit 10, for limiting the position of the governor arm. Adjustments of the parts 14 and 86 thereby de- 55 termine the'relative position of the hand throttle 10 and the full open position of the throttle |1, respectively, it being noted from Figure 2 that in the retracted position of the governor balls 35 the inner ends 31 of the bell cranks 34 6o engage the hub of the pinion gear 30.

From-the above description, it will be apparent that the governor control linkage that I have provided practically eliminates all binding and friction, since there are no parts sliding on one 05 rods 61 and 69 the ends are bent in the same 1, direction, namely, at right angles to the main body of the rod in each case, and the particular advantage of this arrangement is that, the center of pressure and the-center of reaction of the forces imposed are in alignment with the direction of force. This is especially advantageous in the case of the rod 61 against which the tension of the spring 55 acts, for where the points of hearing are arranged in this manner, there is no tendency or uneven wearto occur either on the ends of the rod or the apertured members with which the rod is connected.

While I have shown and described above the structure in. which the principles of the ,present invention have preferablybeen embodied, it is to be understood that my invention is not to be limited to the specific details shown and described, but that, in fact, widely different means may be employed in the practice of the broader aspects of my invention.

What I claim, therefore, and desire to'secure by Letters Patent is:

1. Governor control mechanism for a tractor or the like having a speed responsive governor and a carburetor, said mechanism comprising a throttle rod connected with the carburetor, a governor actuated arm mounted for pivotal movement on the tractor and connected at its outer end with the throttle rod, a leaf spring anchored at its inner end to said governor actuated arm adjacent the pivot axis of the latter, a stop carried by the outer end of said arm and engageable with the leaf spring to limit the relative movement between the arm and spring in "a direction to determine the open position of the 2. Governor control mechanism for a tractor or the like having a speed responsive governor including a governor shaft and a carburetor including a throttle valve, said mechanism comprising a throttle rod connected at one end with said valve, a governor actuated arm including a boss at one end ape'rturedtoreceive said governor shaft and having a longitudinally extending notched section with a. threaded opening formed therein, a set screw disposed in said threaded opening and said notch and adapted when tightened to securely fasten the governor arm to said governor shaft, means connecting the throttle rod with the outer end of said governor arm, whereby the position of the latter determines the throttle opening'ofthe carburetor, a flat leaf spring having. an apertured inner end seated in said notch, the opening in the'spring embracing said set screw, 2, spring clamp disposed in said-notch against the inner end of said leaf, a nut threaded over said set screw and acting against said spring clamp for securing said leaf spring to said arm, a manually adjustable lever movably mounted on the tractor and adapted to retain any position of adjustment,

and a rod member connected between said manually adjustable lever and the outer end of threaded opening formed therein, a set screw disposed in said threaded opening and adapted when tightened to securely .fasten the governor arm to said governor shaft, means connecting the throttle rod with the outer end of said governor arm, whereby the position of the latter determines the throttle opening of the carburetor, a flat leaf spring having an apertured inner end embracing said set screw, a nut threaded over said set screw and acting against said leaf spring for securing the same to said arm, a manually adjustable lever movably mounted on the tractor and. adapted to retain any position of adjustment, and a rod member connected between sasd manually adjustable lever and the outer end of said spring.

4. An article of manufacture comprising a governor arm having an apertured boss and a spring receiving groove at one end, a threaded set screw opening extending from the bottom of said groove and intersecting the opening in said boss, a set screw threaded into said opening, a spring mounted in said groove, and means reacting against said set screw for securing the spring in said groove.

5. An article of manufacture comprising a governor arm having an apertured boss and a spring receiving groove at one end, a threaded set screw opening extending from the bottom of said groove and intersecting the opening in said boss, a set screw threaded into said opening, a spring mounted in said groove, means reacting against said set screw for securing the spring in said groove, a spring engaging projection formed at the outer end of the arm, said spring extending beyond said projection, and an eye formed in the outermost end of said spring.

6. An article of manufacture comprising a governor arm having an'apertured boss at one end, a threaded set screw opening intersecting the opening in said boss, a set screw threaded into said opening, a spring having'an opening receiving said set screw, means reacting against said set screw for securing the spring to said arm, a spring-engaging projection formed at the outer end of the arm, said spring extending beyond said projection, and an eye formed in the outermost end of said spring.

7. Governor control mechanism for a tractor or the like having a speed responsive governor including a governor shaft and a carburetor including a throttle valve, said mechanism comprising a governor actuated arm apertured to receive said governor shaft, means operatively connecting said arm with said throttle valve, whereby the position of said arm determines the throttle opening of the carburetor, a spring, means fixing one end of said spring to said arm and said arm to the governor shaft, a manually adjustable lever movably mounted on the tractor and adapted to retain any position of adjust ment, and means connected between said manually adjustable lever and the outer end of said spring.

8. Governor control mechanism for a tractor or the like having a speed responsive governor and a carburetor having a throttle valve, said mechanism comprising a governor-actuated arm operatively connected to open and close said throttle valve, a fixed pivot on the tractor for said governor-actuated arm, a flexible spring member fixedly anchored at one end to said arm adjacent its pivot, a control lever connected to the other end of said spring member to govern the amount of force'exerted by the spring member against the arm in any given position of the latter, and means serving'as a stop carried by the arm and 'engageable with said spring member-to cooperate with said control lever in limiting the openposltion of the throttle valve.

9. Governor control mechanism for a. tractor or the like having a speed responsive governor and a carburetor having a throttle valve, said I and a carburetor having a ,th'rottle valve, said mechanism comprising a throttle rod connected with the throttle valve, a governor-actuated arm connected with the throttle rod, a leaf spring member anchored at its inner end to said arm,

said arm being swingable in a direction to close the throttle valve of the carburetor against the bias of said leaf spring member and engaging the latter when moved in the other direction,

whereby movement of the governor arm in said other direction is limited, and a manually set lever connected with said leaf spring member to govern the bias imposed on said governor arm by said spring when said arm is moved to close said throttle valve.

11. Governor control mechanism for a tractor f or the like having a speed responsive governor and a carburetor having a throttle valve, said mechanism comprising a governor-actuated arm mounted for movement about a pivot on the tractor and operatively connected to open and close said throttle valve, a flat flexible spring member fixedly anchored at one end to said arm adjacent its pivot and adapted to oppose closing movement of the valve, and a control lever connected with said spring member outwardly of the connection of the latter with said arm for governing the amount 01' force exerted by the '0 spring member against the arm in any given position 01' the latter.

ELMER MCCORMICK. 

